The present invention generally relates to an electrical filter and more particularyly, to an LC (i.e inductance L and capacitance C) filter compact in size and readily manufactured at high reliability and especially suitable for use in a loss distribution transmission circuit and the like.
Conventionally, a typical LC filter of this kind has a construction, for example, as illustrated in FIG. 1, and includes a central or throug-conductor t, a cylindrical ferrite member f fitted, at its central bore, over the through-conductor t, a dielectric member d disposed over the outer peripheral surface of the ferrite member f, and an electrode layer e further provided over the outer pheripheral surface of the dielectric material layer d, therby to form the LC filter between the electrode layer e and the through-conductor t.
In the known LC filter described above, the number of parts involved in the filter and consequently, the time required to assemble the filter are high since the ferrite member f for providing the inductance L and the dielectric member d for providing the capacitance C are respectively formed into separate parts. AS a result, the filter is not of compact size and is not efficient to produce. Moreover, due to the use in some cases of discrete LC parts for assembly, the resultant LC filters tend to be lown in strength, and without sufficient reliability.